1. Field of the Invention
The present invention relates to lighter than air balloons. More specifically, the balloons are constructed from a polymeric film material which has coated thereon a barrier material having an oxygen transmission rate of less than 0.5 cm.sup.3 /100 in.sup.2 /24 hr. at 75.degree. F., 65% relative humidity. The film material may also be used for other applications such as food and beverage packaging.
2. Technology Description
Conventional lighter than air balloons are typically produced by filling an elastomeric material with a helium containing gas to enable the balloon to "float". Such balloons may be used for novelty purposes and are commonly sold at fairs, circuses, restaurants, gift shops, and the like. While these balloons are still in great use, they are relatively limited in their appearance and by their limited lifetime as a result of helium diffusing through the elastomeric material. Elastomeric balloons have also been used for technical applications, e.g., carrying weather instruments to the upper atmosphere.
Within the past 20 years, a new form of balloon made from polymeric film materials has been produced which has been extremely successful as a premium item. Such balloons are typically constructed of Nylon-6 and have coated thereon a metal layer to reduce the rate of helium diffusion and give the balloon a more attractive appearance. As novelties, these balloons are generally sold for special holidays such as birthdays, graduations, anniversaries, Valentine's Day, and the like at card shops, florists, and other shops. Metallized nylon-6 and metallized polyester films are used for technical applications as well. The key criteria for such balloons is that they be constructed of a material which will float when filled with helium and also be relatively gas impermeable to enable to helium to remain in the interior of the nylon film for extended periods of time.
Examples of such premium novelty balloons are described in the literature. U.S. Pat. Nos. 4,077,588 and 4,290,763 disclose a laminate of a nonelastomeric continuous polymer film having coated thereon a metal film. U.S. Pat. No. 4,693,695 discloses an ascending and descending balloon made from this laminate material.
U.S. Pat. No. 5,023,118 discloses artificial flowers made from non-elastomeric polymer sheets whose inner surfaces are coated with continuous metallic coatings. Laminates having multiple polymer sheets and/or metallic coatings are also suggested for use.
In the case of metallized nylon balloons, both the metal layer and the nylon substrate provide the barrier to helium penetration. Balloons made from metallized polyester have relied heavily on the metal layer for the barrier until now.
A fundamental desire is to provide a material which has a lower weight to area ratio to allow smaller, flotable balloons as well as move innovative shapes. A secondary desire is to reduce the cost of raw materials when producing such premium novelty balloons. More specifically, it would be desirable to produce premium novelty balloons from polymers that are lighter than nylon on a per unit area basis.
Accordingly, there exists a need in the art for balloons which are made from polymeric substrate film materials, are produced from relatively inexpensive raw materials, and can float for extended periods of time.